1. Field of the Invention
The present invention relates to a connector in which a terminal fitting is locked by a locking portion.
2. Description of the Related Art
A known connector has a resin housing formed with a cavity and with a resin lock that cantilevers into the cavity. The connector further includes a terminal fitting with a rectangular tubular portion configured for insertion into the cavity. A wall of the tubular portion is embossed to define a locking projection that is engaged from behind by a leading end of the resin lock when the terminal fitting is inserted into the cavity. The resin lock exhibits a resilient rigidity and, therefore, keeps the terminal fitting locked. A connector of this construction is disclosed, for example, in Japanese Unexamined Patent Publication No. 2000-294334.
A demand exists for making connectors smaller. A size reduction can be achieved by reducing the thickness of the resin lock in the projecting direction of the locking projection. However, the resilient rigidity and reliability of the resin lock is reduced if the resin lock is thinned. Thus, the leading end of the thinned resin lock may be deformed away from the locking projection of the terminal fitting if an excessive withdrawing force acts on the terminal fitting.
In view of the above situation, an object of the present invention is to ensure reliability of a locking function by a locking portion even if the locking portion is thinned.
The invention is directed to a connector with a housing that preferably is formed from a synthetic resin. The housing has at least one cavity formed with a resiliently deformable lock that cantilevers along an inner wall of the cavity. At least one terminal fitting can be inserted into the cavity. The terminal fitting has a locking surface that projects from an outer surface of the terminal fitting at an angle, and preferably substantially at a right angle. The leading end of the lock engages the locking surface to lock the terminal fitting in the cavity. The leading end of the lock is formed with a wedge-shaped biting portion that contacts and/or bites into a recess-shaped corner formed by an outer surface of the terminal fitting and the locking surface when the terminal fitting is moved in a withdrawing direction.
The leading end of the lock is pushed from the projecting or outer end toward the base or inner end (toward the outer surface of the terminal fitting) if a force acts on the terminal fitting in a withdrawing direction. Thus, there is no possibility of the lock being disengaged from the locking surface, even if the lock is thinned to reduce its resilient rigidity, and a highly reliable locking is provided.
A surface of the biting portion opposed to the locking surface preferably is slanted to approach the locking surface as it extends from its projecting or outer end toward its base or inner end. Thus, the resin lock is pushed toward the outer surface of the terminal fitting by the inclination of this slanted surface when a force acts on the terminal fitting in the withdrawing direction.
The base end of the locking surface preferably is cut obliquely to form a wedge-shaped recess that corresponds to the biting portion between the obliquely cut surface and the outer surface of the terminal fitting. As a result, the biting portion fits into the recess and a displacement of the biting portion with respect to the locking surface is restricted more securely. The wedge-shaped recess preferably is inclined such that a displacement of the locking portion is prevented.
The terminal fitting preferably comprises a locking surface wall on which the locking surface is provided and a reinforcing wall on an inner part of the terminal fitting is substantially in contact with the locking surface wall.
The locking surface wall comprises a notch that preferably extends over substantially the entire width of the locking surface wall to at least partly expose the reinforcing wall.
A length of an engaging surface preferably is the sum of a projecting distance of the locking surface and a thickness of the locking surface wall.
According to a further embodiment, the terminal fitting is formed with a beveled portion that has a slanted surface extending in a direction oblique to a terminal insertion direction.
Preferably, an angle of inclination of the slanted surface to the terminal inserting direction is smaller than an angle of inclination between the terminal insertion direction and a trace of displacement of an extending end of the lock during its resilient restoration.
These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments.